The present invention relates generally to a passenger seat configured to adjust between an upright sitting position and a lie flat sleeping position, and more particularly, to an aircraft seat having independent rollers attached to the seat pan and backrest configured to travel along guides of fixed frame rails to control the angle of the seat an and backrest during recline.
Premium class passenger seats such as those found on airliners can be configured to adjust between an upright sitting position for taxi, take-off and landing (TTOL), and a lie flat sleeping position during flight. In the upright sitting position, the backrest is nearest vertical and the seat pan, or seat bottom, is at a shallow angle to horizontal. As the backrest reclines, the seat pan can be driven forward, and in some configurations, tilts farther from horizontal to cradle the passenger. In the lie flat sleeping position, the support surfaces of the seat pan, backrest and optional leg rest are generally coplanar, and can be horizontal.
Seat recline, seat pan angle and backrest angle are typically controlled by linkage arranged below the seat pan and/or behind the backrest. The seat pan and backrest rest can be pivotally attached such that seat pan movement drives backrest movement, or vice versa. In any conventional arrangement, under-seat and/or behind-seat linkage complicates the seat design and makes it difficult to customize the relationship between the seat pan angle and the backrest angle in the various sitting positions between upright and lie flat. Therefore, what is needed is a simplified way of supporting the seat pan and backrest while controlling the angles thereof during seat recline.